Abstract: The invention concerns a rotor blade for a water turbine with a hydrodynamic profile, to which a suction side and a pressure side are associated, comprising a plurality of overflow channels, which are arranged in the hydrodynamic profile and create a hydraulic connection between the suction side and the pressure side and to which a valve arrangement is associated respectively. The invention is characterised in that the valve arrangement is closed below a preset load limit threshold for the rotor blade and is opened above the load limit threshold, whereas every overflow channel with the valve arrangement in the open position reduces the power coefficient and/or the thrust coefficient of the rotor blade with respect to the closed position.

Abstract: An absorber rod for nuclear reactors with a pile of spherical fuel elements, which is inserted directly into the pile, in order to affect the prevailing neutron flux by absorber material located in an annular gap between two concentric cylindrical rod elements. The absorber rod has concentric rod elements arranged in pairs, a common rod tip and common connecting pieces. The rod elements are cooled by flow of gas and the inner cylindrical rod element performs the support function, i.e., it absorbs and transmits forces and moments originating in the movements of the rod during insertion and extraction.